How hard is it to change a starter on a mercruiser 3.0 liter inboard engine?

Depends on the boat. Some layouts are easy, some not. Here is the procedure:

disconnect battery negative terminal.

Remove rear bracket from the engine block.

remove 2 mounting bolts from the starter body. If there are shims between the starter and engine block, save them.

Disconnect wiring from starter.



Installation is the reverse, use new mounting bolts, use the shims. Do not over-torque the mounting bolts (approx 30 ft lbs).